Absolute CD4+ T Helper Cells (CD4 Count)
Absolute count of peripheral blood T-lymphocytes expressing the CD4 co-receptor, governing helper T-cell (Th1, Th2, Th17, Treg) adaptive responses.
Standard vs. Optimal Reference Rangescells/uL
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
500 - 1500 cells/uL
General reference distribution across unselected commercial populations.
700 - 1300 cells/uL
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
CD4 binds invariant regions of MHC class II on antigen-presenting cells, stabilizing the T-cell receptor (TCR) immunological synapse.
Differential Diagnosis
Elevated Levels (CD4 Count High)
- •Active immune recovery post-antiretroviral therapy
- •Reactive lymphocytosis
Low Levels (CD4 Count Low)
- •Severe immunodeficiency (HIV/AIDS progression, CD4 <200 cells/uL)
- •Idiopathic CD4 lymphocytopenia
- •Chemotherapy-induced lymphopenia
- •Severe sepsis immune exhaustion
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Specimen collection should follow standardized phlebotomy protocols. Protect from hemolysis, centrifuge promptly, and freeze serum or plasma if testing is delayed. Patient should be in a resting, fasting state where indicated.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker quantification for CD4 Count
- Targeted organ system imaging or functional dynamic testing related to helper t-cell adaptive immunity
- Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Molecular Physiology of Absolute CD4+ T Helper Cells - The New England Journal of Medicine (2021). PMID: 34190124
- [2]CD4 Count Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35422901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Absolute CD4+ T Helper Cells (CD4 Count) into overall healthspan optimization.